Heater not working

Tiny
JOSEARIAS
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  • 2002 FORD EXPEDITION
  • V8
  • 2WD
  • AUTOMATIC
  • 136,000 MILES
I have replaced blend door actuator, t stat, heater core valve, flushed hoses, flushed heater core, actuator is doing what suppose to, temperature **** is okay. What else could prevent heater not to work?
Saturday, December 18th, 2010 AT 3:50 PM

8 Replies

Tiny
MJR346
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If both hoses are hot at the heater core outside, I'd look at the actuator again. Seen many of them where if not under a bind will turn but put a slight bind on them and they make a ratchiting sound and won't move. Please give more info on temperature of hoses.
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Thursday, December 6th, 2018 AT 5:21 PM
Tiny
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Both hoses are hot at the heater core outside.
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Thursday, December 6th, 2018 AT 5:21 PM
Tiny
MJR346
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Then I would look for an internal issue. As I stated about the blend door actuator motor, it will turn free, but put a slight bind and normally it won't turn, I change them a lot, but if both sides are hot at the heater core, I would recommend investigating inside issues such as the actuator, the door (which you replaced) or the control head
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Thursday, December 6th, 2018 AT 5:21 PM
Tiny
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What is the function of the actuator? Blend door appears to be opening fine. Sometimes I do hear the ratching sound but not all the time. Should I just go ahead and replace the heater core and the actuator?
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Thursday, December 6th, 2018 AT 5:21 PM
Tiny
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I am getting only (72f) degress coming out of the vents. I am about to give up. What else should I do?
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Thursday, December 6th, 2018 AT 5:21 PM
Tiny
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To be honest I believe the hoses are all about the same temperatures as other hoses outside. If I step on the gas temperature coming out of the vents goes up to 74f and drops back to 68f?
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Thursday, December 6th, 2018 AT 5:21 PM
Tiny
MJR346
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That's why I asked about the temperature of the hoses for. If both going into the firewall with engine temperature at mid range should be too hot to handle on both hoses if the core is operating properly.

If you are hearing the ratchiting, it's probably the actuator. The actuator moves the blend door using a electrical motor. These things are known to strip out the plastic gear built into them and will ratchet and make noise or cause luke warm temperatures.
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Thursday, December 6th, 2018 AT 5:21 PM
Tiny
JACOBANDNICKOLAS
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Mjr346 is correct. If both hear core hoses are hot, the heater core has to be hot too. Thus, the only other thing left is the blend door actuator. As he mentioned, if you hear a ratcheting sound, something is slipping. Most likely the plastic gear that is built into them.
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Thursday, December 6th, 2018 AT 5:21 PM

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